This article is part of the seminar-workshop on the “Consequences of Small Farm Mechanization on Production, Employment and Incomes in the Philippines” sponsored jointly by the Ministry of Agriculture, the National Economic and Development Authority, the Philippine Institute for Development Studies and the International Rice Research Institute held on December 1-2, 1983 at Tagaytay City. It investigates the differences in yield, inputs and cropping intensity for alternative mechanization classes for both rainfed and irrigated areas. Survey area covers Nueva Ecija where a sufficient number of tractors in both areas are found.